Apparatus for reaming holes drilled in the earth



A. M. SHOOK Aug. 12, 1958 APPARATUS FOR REIAMING HOLES DRILLED IN THEEARTH Filed Jan. 8 953 o oooooo IN VEN TOR. A as 715A M. 5/400 AKI'TORNEY 2,847,189 APPARATUS non nEAMrNe HOLES DRILLED IN THE EARTHAusten M. Shook, Houston, Company, New York, N. ware Y., a corporationof Dela- Application .iamlary s, 1953, Serial No. 330,213 4 Claims. (Cl.255-76) The present invention relates to a novel apparatus for reamingout a hole which from a relatively small diameter to a relatively. largediameter. More particularly the invention concerns such an apparatuswhereby an enlarged storage cavity can be ormed below the surface of theearth for receiving liquids such as liquefied petroleum gases which areto be stored.

It has been suggested that liquefied petroleum gases be stored in largecavities formed in earth formations such as beds of salt, clay, orlimestone below the surface of the earth. For example, such a cavity canbe formed about 1,000 feet below the surface and can have'dimensionssuch as 1,000 feet in length by 20 feet in diameter so as to store morethan 50,000 barrels of liquid.

One method for creating such cavities involves first drilling a hole ofrelatively surface of the earth down into the formation within which thecavity is to be formed, then circulating water or othermaterial-removing wash liquid down through the drilled hole to dissolveor otherwise remove material, and concurrently, and continuouslywithdrawing from the hole the liquid containing removed material in adissolved or suspended state. Plain water can be used for removing salt.A material such as clay requires a deflocculant liquid such as water,preferably including a deflocculation promoter such as the molecularlydehydrated phosphates. Limestone requires an acid solution such as awater solution of hydrochloric acid.

While cavities have been successfully formed as described, the speed ofthe operation is often less than desired, and it is diflicult to controlthe shape of the cavity so as to obtain a known uniform diameterthroughout its length. Low speed may be partly attributed to the factthat when operating with a liquid-filled cavity it has not been possibleto employ the eroding action of wash liquid jets impinging directlyagainst the walls of the hole, since the pool of liquid arrests themotion of such jets after they leave a central wash pipe.

In accordance with the present invention there is provided a novelapparatus for enlarging the diameter of a hole drilled into a bed ofsalt, clay, or the like, for progressively scraping material fromsuccessive areas of an annular zone which extends laterally outwardlyfrom the hole while concurrently directing one or more flowing streamsof a material-removing wash liquid, such as water, against substantiallythe full width of the annular zone. The enlarged diameter is extendedlengthwise of the hole by similarly removing material from successivelyexposed annular zones. During the scraping and washing action a pool ofthe wash liquid accumulates in the hole to receive the removed materialand form a suspension or solution which is continuously discharged fromthe hole by the application of air orliquid pressure, by pumpingmechanically, or in any other suitable way.

'- My novel apparatus comprises a stem which is secured on the lower endof a conventional h HOW drill string,

Tex., assignor to The Texas.

has been drilled in the earth,

small diameter from the Patented Aug. 12, 1958 and one or more armsmounted adjacent the bottom of the Stem for lateral 'movementtransversely into contact with the wall of the hole. Each arm has acutting edge extending longitudinally along one of its sides forscraping material from an annular zone extending laterally out from thehole, and also has one or more ports in the opposite side of the arm forprojecting a fluid, such as water, at high velocity in a direction awayfrom the cutting edge and against the annular zone. The

fluid discharged from these ports not only acts to wash ofi loosematerial and to impregnate and soften the wall, but also suppliespropulsive force for assisting rotation of the arm about thelongitudinal axis of the stem.

The apparatus also comprises mechanism (not shown) for rotating the stemabout a longitudinal axis, and for moving the stem longitudinally up ordown so as to extend the reaming operation lengthwise of the hole.Mechanism of the type conventionally employed for rotating and advancingoil well drilling tools can be used.

In the drawings:

'Fig. 1 is a vertical sectional view, parts being in side elevation, ofapparatus embodying the invention, shown in position for reaming out ahole;

Fig. 2 is a cross-sectional view 2-2 of Fig. 1; and

Fig. 3 is a side elevational view of an extension arm which may be addedto the apparatus shown in Fig. 1.

More specifically in accordance with the invention a hole 11 is drilledin a conventional manner from the surface of the earth down into theformation of salt, clay taken along the line or the like, in which astorage cavity is to be formed, and

' end of the drill string is replaced with the reaming apparatus of thepresent invention, which includes a longitudinal stem 17 mounted on thelower end of the drill string and carrying a pair of oppositely disposedtransversely movable reamer arms 19 adjacent its lower end for engagingthe wall 21 of the hole.

Stern 17 includes a cylinder portion 22 within which works alongitudinally movable control piston 23 mounted on a hollow piston rod25 which is journaled in sealing bearings 27 and 29 to prevent theleakage of liquid.

Liquid such as Water is supplied through the hollow drill string to theinterior of stem 17, flows down through the open top 33 of piston rod25, and thence is discharged into cylinder 22 through a plurality ofapertures 35 in the side walls of the piston rod between piston 23 andlower bearing 29.

Piston rod 25 extends down to a position below bearing 29 where it isvconnected to the reamer arms 19 by a pair of oppositely extending links37 and 38. Links 37 and 38 are pivotally secured at their inner ends toopposite sides of piston rod 25, and.at their outer ends are pivotallysecured to arms 19 near their outer ends.

Arms 19 are pivotally connected at their inner ends to the stem 17 byleak-proof ball and socket joints 39 and 41 which have apertures 43registering with connecting slots 45 through which liquid flows from theinside of cylinder 22 to the insides of the arms. This liquid is thendischarged through a plurality of upwardly tilted closely spaced portsor orifices 47 along one side of each arm as a substantially continuoussheet to impinge against substantially the entire area swept over by thearm. The opposite side of the arm 19 is provided with a sharp .cuttingedge 48 which is tilted up to cut into the roof of the cavity 53 beingformed. Cutting edges 48 of the two arms 19 both point in the directionof rotation, and orifices 47 point in the opposite direction to add thepropulsive force of the liquid jets to the force rotatingstern 17. Asshown in Fig. 2 the ports 47 lie above the bisector of the angleincluded by the sides of cutting edge 48.

When the reaming apparatus is inserted in the hole 11 the piston 23 isin lowered position so that the arms 19 are folded into a pair oflongitudinal recesses 49 in the sides of stem 17. Once the reamingapparatus has reached the position at which enlargement is to begin,liquid such as water is introduced into the stem 17 from the drillstring, passes down through the piston rod 25, and forces the piston 23upwardly so as to raise the arms 19 into scraping contact with the sidewalls of the hole. Meanwhile liquid flows through the passages 50 insidearms 19 and is discharged with considerable force from the orifices 47against the walls of the hole to wash away material and to softenmaterial in preparation for the action of the scraping edges 48 of thearms 19 as the stem 17 is rotated.

The washing and scraping action is extended around the circumference ofthe hole to remove material from successive areas of an annular zoneextending laterally outwardly from the hole by rotating the stem 17while maintaining the liquid pressure on piston 23 to hold out the arms19. As material is removed the arms 19 are gradually forced out fartheruntil they are fully extended.

To extend the reaming operation lengthwise-of the hole once the arms 19have expanded to their fullest extent the stem 17 is raised so that thearms remove material from successively exposed annular zones. Upwardmovement of this type is required when the cutting or scraping edges 48of the blades are tipped upwardly in the direction of rotation, so thatan enlarged cavity 53 is formed having a conical roof 55 from which thescraper edges 48 remove material. Continuous raising of stem 17 causesarms 19 to pursue a spiral path, which is an advantageous procedure.However, intermittent upward movement of stem 17 in small increments canalso be used successfully.

The orifices 47 are so designed in the modification illustrated thatthey are inclined upwardly and rearwardly with respect to the directionof rotation so as to discharge high velocity liquid jets against theroof 55 in a direction opposite the edges 51. The liquid should bedischarged from orifices 47 with sufficient force and velocity to assistin propelling the arms 19 around within the hole.

It is evident that similar apparatus could be used to enlarge a cavityin a downward direction by providing a scraping edge 48 which isinclined downwardly so as to scape the fioor of the cavity; and bytilting the orifices 47 downwardly so as to wash the floor of thecavity. Relocation of links 37 and 38 obviously would then be requiredto clear the arms.

The liquid injected from the orifices 47 gradually accumulates until itforms a deep pool filling the enlarged cavity 53 and the portion of thehole 11 surrounding the stem 17 and the drill string. The continuedaddition of liquid under pressure then forces liquid from the pool tothe surface of the earth where it is discharged. If the material of theformation is soluble, for example salt, the dissolved salt is carried tothe surface in solution as a concentrated brine. If the material isinsoluble, for example clay, the finely divided removed particles arecarried to the surface as a suspension in the liquid.

The procedure wherein the roof of the cavity is scraped and the cavityis enlarged upwardly is particularly advantageous when operating with acavity full of liquid because the material removed from the roof dropsdown into the liquid to become dissolved or suspended therein. Whenoperating on the floor of the cavity the removed material may tend toaccumulate as a mud.

Sometimes the diameter of the cavity 53 must be enlarged to a greaterextent than is possible with the arms 19. Therefore provision is madefor coupling an extension to each arm, which is accordingly providedwith a threaded bore 57 in its outer end normally closed by a plug 59.The reaming apparatus is withdrawn from the hole 11, the plugs 59 areremoved, and an extension arm 61, shown in Fig. 3, is threaded intoplace in the end of each of the arms 19. The extension arm 61 isidentical to the arms 19 with respect to the construction of itsscraping edge 63 and the line of orifices 65, both of which are alignedwith the corresponding parts of arms 19.

The apparatus is then reintroduced into the cavity 53 with the armsfolded in, and the operation of further enlarging the diameter of thecavity proceeds by operating the piston 23 to raise the extended armsagainst the side walls of the cavity, rotating the stem 17 until thearms are fully extended, and then raising the stem 17 gradually.

Obviously, many modifications and variations of the invention ashereinbefore set forth may be made without departing from the spirit andscope thereof, and therefore only such limitations should be imposed asare indicated in the appended claims.

I claim:

1. Apparatus for reaming a hole drilled in the earth comprising arotatable stem; an arm pivotally mounted at a near end on said stem formovement transversely thereof, said arm comprising a blade having sidesinclined together at an angle and meeting in a cutting edge on theleading side of said arm, said cutting edge extending longitudinallyfrom a position adjacent said near end to the far end, both of saidsides also being inclined upwardly when said arm is in extendedposition; said arm also having a plurality of ports spacedlongitudinally along said arm on the lagging side thereof opposite saidcutting edge and above the bisectors of said angle, for projecting afluid at high velocity therefrom in an upward direction transversely ofsaid arm and away from said cutting edge when said arm is in extendedposition, said ports being inclined upwardly to the outlets thereof; andmeans for moving said arm transversely of said stem into and out ofextended cutting position.

2. Apparatus for reaming a hole drilled in the earth comprising arotatable stem; an arm having a near end pivotally mounted on said stemfor movement transversely thereof, said arm having a cutting edge and aplurality of ports for discharging liquid therefrom, said arm having afar end and having coupling means at said far end constructed andarranged for connecting said arm to a hollow reamer extension havingsimilar cutting edge and parts in axial alignment therewith, whereby theeffective length of said arm for reaming is increased thereby to enlargethe diameter of said hole to a greater size than is possible with saidarm, passage means in the far end of said arm in position for deliveringliquid to such an extension after connection thereto, and means closingsaid passage means operable to open said passage means for the deliveryof liquid therethrough.

3. An extension for reaming apparatus comprising a hollow arm havingmeans at one end thereof for connection to a reamer arm, having passagemeans for receiving fluid from such a reamer arm, having alongitudinally extending cutting edge along one side thereof, and havingorifice means for discharging fluid therefrom transversely of said armand away from said cutting edge.

4. Apparatus for reaming a hole drilled in the earth comprising arotatable tubular stern; an arm having a far end and having a near endpivotally mounted on said stem for movement transversely thereof, saidarm having a cutting edge extending longitudinally from a positionadjacent said near end to said far end; said arm also having port meansfor projecting a liquid therefrom; and means for moving said armtransversely of said stem into and out of cutting position, said lastnamed means comprising a piston movable up and down within said stem, atubular piston rod projecting downwardly from above said piston throughsaid piston to a position below i the bottom of said stem, said pistonrod having apertures l for liquid both above and below said pistonwithin said 3 stem, :1 first seal located between the top of said pistonand the upper of said apertures, a second seal located between the lowerof said apertures and the bottom of said stem, the construction andarrangement being such that when pressure liquid is introduced to theinside of said stem it passes in through the upper of said apertures,down through said hollow piston rod, and out through the bottom of saidapertures and forces said piston upwardly; and linkage means connectingsaid piston rod below said stem to said arm; said arm and the interiorof said stem below said piston having intercommunicating passages forconducting liquid to said port means.

References Cited in the file of this patent UNITED STATES PATENTS1,323,905 Otto Dec. 2, 1919

